In-situ plasma cleaning of process chamber components

ABSTRACT

Provided herein are approaches for in-situ plasma cleaning of ion beam optics. In one approach, a system includes a component (e.g., a beam-line component) of an ion implanter processing chamber. The system further includes a power supply for supplying a first voltage and first current to the component during a processing mode and a second voltage and second current to the component during a cleaning mode. The second voltage and current are applied to one or more conductive beam optics of the component, individually, to selectively generate plasma around one or more of the one or more conductive beam optics. The system may further include a flow controller for adjusting an injection rate of an etchant gas supplied to the beam-line component, and a vacuum pump for adjusting pressure of an environment of the beam-line component.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional of pending U.S. non-provisional patent applicationSer. No. 14/820,747, filed Aug. 7, 2015, which claims priority to U.S.provisional patent application Ser. No. 62/174,906, filed Jun. 12, 2015,the entire contents of the applications incorporated by referenceherein.

FIELD OF THE DISCLOSURE

The disclosure relates generally to techniques for manufacturingelectronic devices, and more particularly, to techniques for improvingthe performance and extending the lifetime of components within aprocessing chamber.

BACKGROUND OF THE DISCLOSURE

Ion implantation is a process by which dopants or impurities areintroduced into a substrate via bombardment. In semiconductormanufacturing, the dopants are introduced to alter electrical, optical,or mechanical property. For example, dopants may be introduced into anintrinsic semiconductor substrate to alter the type and level ofconductivity of the substrate. In manufacturing an integrated circuit(IC), a precise doping profile is often important for proper ICperformance. To achieve a desired doping profile, one or more dopantsmay be implanted in the form of ions in various doses and various energylevels.

A conventional ion implantation system may comprise an ion source and aseries of beam-line components through which an ion beam passes. The ionsource may comprise a chamber where desired ions are generated. The ionsource may also comprise a power source and an extraction electrodeassembly disposed near the chamber. The beam-line components, mayinclude, for example, a mass analyzer, a first acceleration ordeceleration stage, a collimator, and a second acceleration ordeceleration stage. Much like a series of optical lenses that manipulatea light beam, the beam-line components can filter, focus, and manipulateions or ion beam having desired species, shape, energy, and otherqualities. The ion beam that passes through the beam-line components maybe directed toward a substrate that is mounted on a platen or clamp. Thesubstrate may be moved in one or more dimensions (e.g., translate,rotate, and tilt) by an apparatus, sometimes referred to as a roplat. Itshould be appreciated by those skilled in the art that the entire pathtraversed by the ion beam is typically evacuated during ionimplantation.

The ion implanter system is required to generate a stable, well-definedion beam for a variety of different ion species and extraction voltages.It is therefore desirable to operate the ion source for extended periodsof time without the need for maintenance or repair. After several hoursof normal operation using source gases (such as AsH₃, PH₃, BF₃, andother species), beam constituents eventually create deposits on beamoptics. Beam optics within a line-of-sight of the wafer also becomecoated with residues from the wafer, including Si and photoresistcompounds. These residues build up on the beam-line components, causingspikes in the DC potentials during normal operation (e.g., in the caseof electrically biased components) and eventually flake off, causingincreased particulate contamination to be transferred to the wafer.

One way to prevent the effect of the material accumulation is tointermittently replace beam-line components of the ion implanter system.Alternatively, beam-line components may be manually cleaned. However,these measures require the ion source or the entire ion implanter systemto be powered down and to release the vacuum within the system.Moreover, the ion implanter system, after replacing or cleaning thebeam-line components, must be powered and evacuated to reach operationalcondition. Accordingly, these maintenance processes may be very timeconsuming. In addition, the beam-line component is not used during themaintenance processes. As such, frequent maintenance processes maydecrease the time available for IC production, while increasing overallmanufacturing cost.

SUMMARY

In view of the foregoing, it would be advantageous to provide a systemand method for in-situ plasma cleaning of ion beam-line components(e.g., ion beam optics), wherein the in-situ plasma cleaning may beperformed over a short time and without having to vent and/or manuallyclean the ion beam optics. Moreover, it would be advantageous to providea system and method for in-situ plasma cleaning of ion beam opticswherein a plasma is locally generated in an area surrounding just thosecomponents that need to be cleaned, thereby reducing unwanted etching toother components of the beam-line.

An exemplary ion implanter in accordance with the present disclosure mayinclude a beam-line component including a chamber for generation of aplasma, a power supply in communication with the chamber. The powersupply may be configured to supply a first voltage and a first currentto the beam-line component during a processing mode and a second voltageand a second current to the beam-line component during a cleaning mode,wherein the second voltage and the second current are applied to aplurality of conductive beam optics of the beam-line component, inparallel, to generate a plasma around the plurality of conductive beamoptics.

An exemplary system in accordance with the present disclosure mayinclude a beam-line component including a chamber for generation of aplasma, wherein the beam-line component includes a plurality ofconductive beam optics disposed along an ion beam-line. The system mayfurther include a power supply in communication with the chamber, thepower supply configured to supply a first voltage and a first current tothe beam-line component during a processing mode and a second voltageand a second current to the beam-line component during a cleaning mode.The second voltage and the second current may be applied to one or moreof the plurality of conductive beam optics, in parallel, to generate aplasma around the one or more of the plurality of conductive beamoptics. The system may further include a flow controller for adjustingan injection rate of an etchant gas supplied to the beam-line component,and a vacuum pump for adjusting a pressure of the beam-line component.

An exemplary method in accordance with the present disclosure mayinclude providing a beam-line component including a chamber forgeneration of a plasma, and supplying a first voltage and a firstcurrent to the beam-line component during a processing mode. The methodmay further include supplying a second voltage and a second current tothe beam-line component during a cleaning mode, wherein the secondvoltage and the second current are applied to a plurality of conductivebeam optics of the beam-line component, in parallel, to selectivelygenerate a plasma around the conductive beam optics.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view illustrating an ion beam-line system inaccordance with the present disclosure.

FIG. 2A is a semi-transparent isometric view illustrating a chamber ofthe ion beam-line system shown in FIG. 1.

FIG. 2B is a semi-transparent isometric view illustrating a chamber ofthe ion beam-line system shown in FIG. 1.

FIG. 3 is a side cross-sectional view illustrating ion beam optics ofthe ion beam-line system shown in FIG. 1 in a processing mode.

FIG. 4 is a side cross-sectional view illustrating ion beam optics ofthe ion beam-line system shown in FIG. 1 in a cleaning mode.

FIG. 5A is an illustration of plasma generation around the ion beamoptics of the ion beam-line system shown in FIG. 1.

FIG. 5B is an illustration of plasma generation around the ion beamoptics of the ion beam-line system shown in FIG. 1.

FIG. 6A is an image illustrating accumulation of a deposit on an ionbeam optic of the ion beam-line system shown in FIG. 1.

FIG. 6B is an image illustrating the one of the ion beam optics shown inFIG.

6A following removal of the deposit.

FIG. 7 is a side cross-sectional view of an electrode grid of the ionbeam-line system shown in FIG. 1.

FIG. 8 is a flowchart illustrating an exemplary method according to thepresent disclosure.

The drawings are not necessarily to scale. The drawings are merelyrepresentations, not intended to portray specific parameters of thedisclosure. The drawings are intended to depict typical embodiments ofthe disclosure, and therefore should not be considered as limiting inscope. In the drawings, like numbering represents like elements.

DETAILED DESCRIPTION

A system and method in accordance with the present disclosure will nowbe described more fully hereinafter with reference to the accompanyingdrawings, where embodiments of the system and method are shown. Thesystem and method, however, may be embodied in many different forms andshould not be construed as being limited to the embodiments set forthherein. Rather, these embodiments are provided so this disclosure willbe thorough and complete, and will fully convey the scope of the systemand method to those skilled in the art.

For the sake of convenience and clarity, terms such as “top,” “bottom,”“upper,” “lower,” “vertical,” “horizontal,” “lateral,” and“longitudinal” will be used herein to describe the relative placementand orientation of these components and their constituent parts, eachwith respect to the geometry and orientation of a component of asemiconductor manufacturing device as appearing in the figures. Theterminology will include the words specifically mentioned, derivativesthereof, and words of similar import.

As used herein, an element or operation recited in the singular andproceeded with the word “a” or “an” should be understood as notexcluding plural elements or operations, unless such exclusion isexplicitly recited. Furthermore, references to “one embodiment” of thepresent disclosure are not intended to be interpreted as excluding theexistence of additional embodiments also incorporating the recitedfeatures.

As stated above, provided herein are approaches for in-situ plasmacleaning of components of an ion implantation system and/or within aprocess chamber. In one approach, a system includes a component operablewith a chamber for generation of a plasma. The system further includes apower supply for supplying a first voltage and first current to thecomponent during a processing mode and a second voltage and secondcurrent to the component during a cleaning mode. The second voltage andcurrent are applied to a conductive line optic of the component toselectively generate plasma around the conductive beam optics. Thesystem may further include a flow controller for adjusting an injectionrate of an etchant gas supplied to the beam-line component, and a vacuumpump for adjusting pressure of the component. By optimizing the pressureand the injection rate, a more controlled distribution of the plasmaaround the component may be achieved, which increases overall etchingaccuracy.

Referring now to FIG. 1, an exemplary embodiment demonstrating a system10 for performing in-situ plasma cleaning of one or more components ofthe system in accordance with the present disclosure is shown. Thesystem 10 represents a process chamber containing, among othercomponents, an ion implanter and a series of beam-line components 16through which an ion beam 18 passes. An ion source 14 may comprise achamber that receives a flow of gas 24 and generates ions. The ionsource 14 may also comprise a power source and an extraction electrodeassembly disposed near the chamber. The beam-line components 16 mayinclude, for example, a mass analyzer 34, a first acceleration ordeceleration stage 36, a collimator 38, and an energy purity module(EPM) 40, which corresponds to a second acceleration or decelerationstage. Although described hereinafter with respect to the EPM 40 of thebeam-line components 16 for the sake of explanation, it will beappreciated that the embodiments described herein for in-situ plasmacleaning are applicable to virtually any component or surface of thesystem 10.

The beam-line components 16 may filter, focus, and manipulate ions orthe ion beam 18 to have a desired species, shape, energy, and otherqualities. The ion beam 18 passing through the beam-line components 16may be directed toward a substrate that is mounted on a platen or clampwithin a process chamber 46. The substrate may be moved in one or moredimensions (e.g., translate, rotate, and tilt).

As shown, there may be one or more feed sources 28 operable with thechamber of the ion source 14. In some embodiments, material providedfrom the feed source 28 may include source material and/or additionalmaterial. The source material may contain dopant species that may beintroduced into the substrate in the form of ions. Meanwhile, theadditional material may include diluent, which may be introduced intothe ion source chamber of the ion source 14 along with the sourcematerial to dilute the concentration of the source material in thechamber of the ion source 14. The additional material may also include acleaning agent (e.g., an etchant gas) that may be introduced into thechamber of the ion source 14 and transported within the system 10 withor without the source material to clean one or more of the beam-linecomponents 16.

In various embodiments, different species may be used as the sourceand/or the additional material. Examples of the source and/or additionalmaterial may include atomic or molecular species containing boron (B),carbon (C), oxygen (O), germanium (Ge), phosphorus (P), arsenic (As),silicon (Si), helium (He), neon (Ne), argon (Ar), krypton (Kr), nitrogen(N), hydrogen (H), fluorine (F), and chlorine (Cl). Those of ordinaryskill in the art will recognize that the above species are notexhaustive, and other atomic or molecular species may also be used.Depending on the application(s), the species may be used as the dopantsor the additional material. In particular, one species used as thedopants in one application may be used as the additional material inanother application, or vice-versa.

In exemplary embodiments, the source and/or additional material isprovided into the ion source chamber of the ion source 14 in gaseous orvapor form. If the source and/or additional material is in non-gaseousor non-vapor form, a vaporizer (not shown) may be provided near the feedsource 28 to convert the material into gaseous or vapor form. To controlthe amount and the rate by which the source and/or the additionalmaterial is provided into the system 10, a flowrate controller 30 may beprovided.

The EPM 40 is a beam-line component configured to independently controldeflection, deceleration, and focus of the ion beam 18. As will bedescribed in greater detail below, the EPM 40 may include an electrodeconfiguration comprising a set of upper electrodes disposed above theion beam 18 and a set of lower electrodes disposed below the ion beam18. The set of upper electrodes and the set of lower electrodes may bestationary and have fixed positions. A difference in potentials betweenthe set of upper electrodes and the set of lower electrodes may also bevaried along the central ion beam trajectory to reflect an energy of theion beam at each point along the central ion beam trajectory forindependently controlling deflection, deceleration, and/or focus of anion beam.

Referring now to FIGS. 2A-B, the EPM 40 according to exemplaryembodiments will be described in greater detail. As shown, the EPM 40includes an EPM chamber 50, which extends above and encases EPM 40. TheEPM chamber 50 is configured to receive a gas and generate a plasmatherein. In one embodiment, as shown in FIG. 2A, EPM chamber 50 mayreceive a flow of the gas 24 (FIG. 1) from the ion source 14 at a gasinlet 52 through a sidewall 54. In another embodiment, as shown in FIG.2B, EPM chamber 50 may receive a flow of gas 56 at a gas inlet 58through a top section 60 of the EPM chamber 50. The gas 56 may besupplied from a supplementary gas source 62 separate from the flow ofgas 24 from the ion source 14. In this embodiment, an injection rate ofthe gas 56 into the EPM chamber 50 may be controlled by a flowcontroller 64 (e.g., a valve).

EPM 40 further operates with one or more vacuum pumps 66 (FIG. 1) toadjust a pressure of the EPM chamber 50. In exemplary embodiments, thevacuum pump 66 is coupled to the process chamber 46 (FIG. 1), andpressure is adjusted within the EPM chamber 50 through one or moreconduits 70. In another embodiment however, the EPM 40 may include oneor more additional pumps more closely coupled to the EPM chamber 50.

Referring now to FIGS. 3-4, an exemplary embodiment demonstrating thestructure and operation of the EPM 40 in accordance with the presentdisclosure is shown. The EPM 40 includes one or more conductive beamoptics 70A-N, which may include a plurality of graphite electrode rodsdisposed along an ion beam-line/trajectory 72, as shown. In thisembodiment, the conductive beam optics 70A-N are arranged in asymmetrical configuration, wherein the conductive beam optics 70A-Brepresent a set of entrance electrodes, the conductive beam optics 70C-Drepresent a set of exit electrodes, and the remaining beam optics 70E-Nrepresent several sets of suppression/focusing electrodes. In anotherembodiment, the conductive beam optics 70A-N may be arranged in anasymmetrical configuration. As shown, each set of electrode pairsprovides a space/gap to allow the ion beam (e.g., a ribbon beam) to passtherethrough. The conductive beam optics 70A-N are provided in a housing74. As described above, the vacuum pump 66 may be directly or indirectlyconnected to the housing 74 for adjusting a pressure of an environment68 therein.

In exemplary embodiments, the conductive beam optics 70A-N include pairsof conductive pieces electrically coupled to each other. Alternatively,the conductive beam optics 70A-N may be a series of unitary structureseach including an aperture for the ion beam to pass therethrough. In theembodiment shown, upper and lower portions of each electrode pair mayhave different potentials (e.g., in separate conductive pieces) in orderto deflect the ion beam passing therethrough. Although the conductivebeam optics 70A-N are depicted as seven (7) pairs (e.g., with five (5)sets of suppression/focusing electrodes), it should be appreciated thatany number of elements (or electrodes) may be utilized. For example, theconfiguration of conductive beam optics 70A-N may utilize a range ofthree (3) to ten (10) electrode sets.

In some embodiments, the ion beam passing through the electrodes alongthe ion beam-line 72 may include boron or other elements. Electrostaticfocusing of the ion beam may be achieved by using several thinelectrodes (e.g., the suppression/focusing electrodes of conductive beamoptics 70E-N) to control grading of potential along the ion beam-line72. In the configuration of conductive beam optics 70A-N shown, highdeceleration ratios may also be provided while avoiding over-focusing.As a result, use of input ion beams may be used in an energy range thatmay enable higher quality beams, even for very low energy output beams.In one non-limiting example, as the ion beam passes through theelectrodes of the conductive beam optics 70A-N, the ion beam may bedecelerated from 6 keV to 0.2 keV and deflected at 15°. In thisnon-limiting example, the energy ratio may be 30/1.

It should be appreciated that separating and independently controllingdeceleration, deflection, and/or focus may be accomplished by: (1)maintaining symmetry of the conductive beam optics 70A-N with respect toa central ray trajectory (“CRT”) of the ion beam, and (2) varyingdeflection voltages along the CRT of the ion beam to reflect beam energyat each point along the CRT at a deflection angle. Symmetry of theelectrodes with respect to the CRT of the ion beam is where the ends ofupper and lower electrodes closest to the ion beam may be maintained atequal (or near equal) perpendicular distances from the CRT of the ionbeam.

As noted above, one cause of degradation to the system 10 may beexcessive accumulation of deposits or by-products generated by the beamconstituents during use. For example, deposits may accumulate on theconductive beam optics 70A-N of the EPM 40, as well as on othercomponents of the system (FIG. 1). In some embodiments, thisaccumulation of material may be more severe when carborane, SiF₄ or GeF₄is used as the source material. To prevent excessive accumulation, thesystem 10 of the present embodiment may operate in two modes: aprocessing mode and a cleaning mode. During the processing mode, thesystem 10 may operate normally to produce the ion beam 18. During thecleaning mode, the EPM 40, or any other component of the system 10, suchas beam-line components 16, may be in situ cleaned.

Referring again to FIG. 3, the EPM 40 operating under the processingmode according to one embodiment of the present disclosure is shown.During the processing mode, a power supply 76 (e.g., a DC power supply)supplies a first voltage and a first current to the EPM 40 or, morespecifically, to conductive beam optics 70A-N, to generate a plasmawithin the EPM chamber 50 (FIGS. 2A-B). In various embodiments, thevoltage and current provided by the power supply 76 may be constant orvaried. In one embodiment, the conductive beam optics 70A-N are held ata series of DC potentials from 0.1 keV-100 keV.

Referring again to FIG. 4, the EPM 40 operating under the cleaning modeaccording to one embodiment of the present disclosure is shown. In thisembodiment, the EPM 40 is switched from the processing mode to thecleaning mode. The system 10 may include a relay switch (not shown) forswitching between the processing mode and the cleaning mode so as toavoid having to manually switch power cables. In one embodiment,switching from the processing mode to the cleaning mode is performedautomatically, for example, in the case that a predetermined threshold(e.g., a set number of beam glitches) is achieved. In anotherembodiment, the switching can be triggered by an operator.

During the cleaning mode, a second voltage and a second current aresupplied to the conductive beam optics 70A-N of the EPM 40. In oneembodiment, the conductive beam optics 70A-N may be electrically drivenin parallel (i.e., individually) or in series to enable uniform and/orindependent cleaning of the electrodes. The second voltage and thesecond current may be supplied by the DC power supply 76, or by a radiofrequency (RF) power supply 80. Switching from the DC power supply 76 ofthe processing mode to the RF power supply 80 during the cleaning modeminimizes disruptive arcing that may occur during the cleaning cycle.

In exemplary embodiments, the EPM 40 may be in situ cleaned during thecleaning mode. To accomplish this, an etchant gas (e.g., gas 24, 56shown in FIGS. 3A-B, respectively) may be introduced into the EPM 40 ata given flow/injection rate. For example, the etchant gas may beintroduced at a flow rate of about 25 standard cubic centimeters perminute (SCCM) to about 200 SCCM. Preferably, the etchant gas may beintroduced at about 50 SCCM to about 100 SCCM to maintain high pressureflow around the conductive beam optics 70A-N.

Various species may be introduced as the cleaning agent of the etchantgas. The cleaning agent may be atomic or molecular species containingchemically reactive species. Such species, when ionized, may chemicallyreact with the deposits accumulated on the conductive beam optics 70A-N.Although a cleaning agent with chemically reactive species will bedescribed herein, the present disclosure does not preclude utilizingchemically inert species. In another embodiment, the cleaning agent maycontain heavy atomic species which, when ionized, may form ions withhigh atomic mass units (amu). Non-limiting examples of the cleaningagent may include atomic or molecular species containing H, He, N, O, F,Ne, Cl, Ar, Kr, and Xe, or a combination thereof. Preferably, NF₃, O₂,or a mixture of Ar and F₂, or a combination thereof, may be used as thecleaning agent.

The composition of the etchant gas can be chosen to optimize chemicaletching based on a composition of the deposit(s) formed on theconductive beam optics 70A-N. For example, fluorine-based plasmas may beused to etch beam components containing B, P, and As, while oxygen-basedplasmas may be used to etch photoresist. In one embodiment, by adding Aror other heavy species to the plasma mixture, increased ion bombardmentcan help further improve the removal rate of the deposit(s) from theconductive beam optics 70A-N using a chemically enhanced ion sputteringprocess. Plasma or ion bombardment also provokes heating of the surfacesto aid chemical etch rates and help volatilize the deposit(s) from thesurface of the conductive beam optics 70A-N.

Referring now to FIGS. 4 and 5A-5B, generation of a plasma 82 within theEPM 40 according to exemplary embodiments is shown. In the presentembodiment, the plasma 82 may be created in the volume defined by thehousing 74 by providing continuous or pulsed AC/DC voltage to thegraphite electrodes of the conductive beam optics 70A-N. For example,about 400 V to 1 kV at about 1 A to about 5 A of current may be suppliedto the conductive beam optics 70A-N using the DC power supply 76 or theRF power supply 80. The power may be in the form of AC voltage or pulsedDC voltage to the conductive beam optics 70A-N. As stated above, each ofthe conductive beam optics 70A-N may be driven in parallel to enableindependent and selective generation of the plasma 82.

To increase the density and localization of the plasma 82 within the EPM40, a pressure within the EPM 40 is increased. Specifically, as shown inFIGS. 5A-B, by increasing the pressure set point for the cleaningprocess, either by increasing the gas injection rate or reducing thepump rate to the EPM 40, the plasma 82 is localized around thoseelectrode rods that are powered (indicated by an ‘X’). For example, theplasma distribution shown in FIG. 5-A demonstrates a diffusive plasma 82at 20 mTorr, while the plasma distribution shown in FIG. 5-Bdemonstrates a localized plasma 82 in an area 86 surrounding the four(4) powered electrode rods at 1 Torr.

Selective plasma generation is useful to minimize the impact of harmfulradicals (e.g., fluorine) to other parts of the EPM 40, in order toprevent etching and damaging of heavy metal (e.g., steel) parts. Ahigher flow rate through the EPM 40 can allow for faster replacement ofetch by-products with fresh reactants, producing a more efficient cleanprocess.

Furthermore, by generating the plasma near one or more of the conductivebeam optics 70A-N, and supplying the etchant gas to the EPM 40 at anoptimized flow rate, the conductive beam optics 70A-N may be cleaned.For example, as shown in FIGS. 6A-B, chemically reactive radicalscontained in the plasma 82 may remove deposits 90 accumulated on thesurface of one of the conductive beam optics, 70-E, via chemicalreaction. In an exemplary embodiment, the conductive beam optic 70-E isa graphite electrode rod containing surface deposits 90 such as Si,Phosphorus, and photoresist, as shown in FIG. 6-A, which are removed bythe cleaning process, as shown in FIG. 6-B.

In addition, the ions in the cleaning plasma 82 may remove theaccumulated deposit 90 via an ion sputtering process. The heat generatedfrom the cleaning plasma 82 may also enhance the cleaning process as thedeposits accumulated on the conductive beam optics 70A-N may be removedby the heat or may become more volatile with increased temperature. Forexample, as described above, the conductive beam optics 70A-N may beprovided with a voltage of between 400 and 1000V at a current of between1 to 5 amps. Thus, it is possible to generate up to about 5 kW of heat.Thus, by providing highly reactive and/or heavy cleaning species, andgenerating the plasma 82 near the conductive beam optics 70A-N,effective plasma cleaning may be performed. As noted above, a high flowrate by which the cleaning materials are introduced into the EPM 40 mayenhance the cleaning process. This technique, unlike conventionaltechniques, may be performed in situ, and the system 10 (FIG. 1) of thepresent disclosure need not power down, and the vacuum of the entiresystem 10, or a portion of the system 10, may be maintained. This canvary, for example, depending on the gas injection and pumpingconfigurations used, or inclusion of isolation regions. For localizedplasma generation, as shown in FIG. 5, the pressure near the optics thatare being cleaned is at a lower vacuum state than during the processingmode.

Referring now to FIG. 7, a cross-sectional view of the conductive beamoptics 70A-N within the housing 74 will be described in greater detail.In this embodiment, during the cleaning mode, the second voltage (DC,AC, RF etc) can also be applied to an electrode grid 92 disposed betweenthe conductive beam optics 70A-N and the housing 74. For example, theelectrode grid may be a gridded liner that is grounded during theprocessing mode, along with the housing 74. The conductive beam optics70A-N may be at zero volts (or another fixed voltage) with respect thepower supplied to the electrode grid 92 during the cleaning mode. Whenthe processing mode is switched to the cleaning mode, the plasma 82 isformed, as shown.

To increase the density and localization of the plasma 82 within thehousing 74, a pressure of the environment 68 may be increased.Specifically, by increasing the pressure set point for the cleaningprocess, either by increasing the gas injection rate or reducing thepump rate to the housing 74, the plasma 82 may be localized around oneor more of the conductive beam optics 70A-N.

Referring now to FIG. 8, a flow diagram illustrating an exemplary method100 for in-situ plasma cleaning of ion beam optics in accordance withthe present disclosure is shown. The method 100 will be described inconjunction with the representations shown in FIGS. 1-7.

Method 100 includes providing a component operable with a chamber of anion implanter for generating a plasma, as shown in block 101. In someembodiments, the component is a beam-line component, such as an energypurity module (EPM). In some embodiments, the EPM includes a conductivebeam optic. In some embodiments, the EMP includes a plurality ofconductive beam optics. In some embodiments, the plurality of conductivebeam optics includes a plurality of electrode rods.

Method 100 further includes supplying a first voltage and a firstcurrent to the component during a processing mode, as shown in block103. In some embodiments, a first voltage and a first current aresupplied by a direct current (DC) power supply.

The method 100 further includes switching from the processing mode to acleaning mode, as shown in block 105. In some embodiments, the method100 includes automatically switching from the processing mode to thecleaning mode in the case that a predetermined threshold is achieved,e.g., a maximum acceptable number of beam glitches.

Method 100 further includes supplying a second voltage and a secondcurrent to the component during a cleaning mode, as shown in block 107.In some embodiments, the second voltage and the second current areapplied to a conductive beam optic of the component to generate a plasmaaround the conductive beam optic. In some embodiments, the secondvoltage and the second current are supplied from a direct current (DC)power supply or a radio frequency (RF) power supply.

Method 100 further includes supplying an etchant gas to the beam-linecomponent to enable etching of the plurality of conductive beam optics,as shown in block 109. In some embodiments, an injection rate of theetchant gas is adjusted. In some embodiments, a composition of theetchant gas is selected to optimize etching of the component based on acomposition of the deposit formed thereon.

Method 100 further includes adjusting a pressure of an environment ofthe component, as shown in block 111. In some embodiments, the pressuresupplied to the component is increased to localize the plasma in an areasurrounding one or more of the conductive beam optics.

Method 100 further includes etching the component to remove a depositformed on the conductive beam optic during the processing mode, as shownin block 113. In some embodiments, the conductive beam optic is etchedusing an ion sputtering process.

In view of the foregoing, at least the following advantages are achievedby the embodiments disclosed herein. Firstly, the in-situ plasmacleaning may be performed over a short time and without having to ventand/or manually clean the component. Secondly, during in-situ plasmacleaning the plasma density is greater surrounding those components thatare to be cleaned, thereby reducing unwanted etching to other componentsof the beam-line and/or the system.

While certain embodiments of the disclosure have been described herein,the disclosure is not limited thereto, as the disclosure is as broad inscope as the art will allow and the specification may be read likewise.Therefore, the above description are not to be construed as limiting,but merely as exemplifications of particular embodiments. Those skilledin the art will envision other modifications within the scope and spiritof the claims appended hereto.

What is claimed is:
 1. A method, comprising: providing an electrode gridand a plurality of conductive beam optics within an electrostaticfilter, wherein the electrode grid is disposed above and below an ionbeamline, between the plurality of conductive beam optics and a housingof the electrostatic filter; supplying, from a power supply, a firstvoltage and a first current to the plurality of conductive beam opticsduring a processing mode; and supplying a second voltage and a secondcurrent to the electrode grid during a cleaning mode to generate aplasma around one or more of the conductive beam optics, wherein theelectrode grid is grounded during the processing mode and supplied thesecond voltage during the cleaning mode, and wherein the plurality ofconductive beam optics is at zero volts during the cleaning mode.
 2. Themethod of claim 1, further comprising supplying an etchant gas to theelectrostatic filter to enable cleaning of the plurality of conductivebeam optics.
 3. The method of claim 2, further comprising adjusting aninjection rate of the etchant gas using a flow controller.
 4. The methodof claim 1, further comprising arranging electrode grid parallel to theion beamline.
 5. The method of claim 1, further comprising adjusting apressure of the chamber using a vacuum pump.
 6. The method of claim 1,further comprising supplying the second voltage and the second currentfrom one of the following: a direct current (DC) power supply, and aradio frequency (RF) power supply.
 7. The method of claim 6, furthercomprising switching from the processing mode to the cleaning mode,wherein the first voltage and the first current are supplied by the DCpower supply.
 8. The method of claim 1, further comprising etching,during the cleaning mode, a deposit formed on one or more of theconductive beam optics.
 9. A method comprising: providing an electrodegrid and a plurality of conductive beam optics within a chamber of anelectrostatic filter, wherein the electrode grid extends parallel to,and is disposed above and below, an ion beamline; supplying, from apower supply, a first voltage and a first current to the plurality ofconductive beam optics during a processing mode; supplying a secondvoltage and a second current to the electrode grid during a cleaningmode to generate a plasma around one or more of the conductive beamoptics, wherein the electrode grid is grounded during the processingmode, and wherein the plurality of conductive beam optics is at zerovolts during the cleaning mode; and etching, during the cleaning mode, adeposit formed on one or more of the conductive beam optics.
 10. Themethod of claim 9, further comprising adjusting an injection rate of theetchant gas using a flow controller.
 11. The method of claim 9, furthercomprising providing the electrode grid directly adjacent the pluralityof conductive beam optics and a housing defining the chamber of anelectrostatic filter.
 12. The method of claim 9, further comprisingincreasing a pressure of the chamber using a vacuum pump.
 13. The methodof claim 9, further comprising supplying the second voltage and thesecond current from one of the following: a direct current (DC) powersupply, and a radio frequency (RF) power supply.
 14. The methodaccording to claim 9, further comprising automatically switching fromthe processing mode to the cleaning mode in the case a predeterminedthreshold of ion beam glitches is achieved.
 15. A method comprising:providing an electrode grid and a plurality of conductive beam opticswithin a chamber of an electrostatic filter, wherein the electrode gridextends parallel to, and is disposed above and below, an ion beamlinepassing through the plurality of conductive beam optics, and wherein theelectrode grid is directly adjacent the conductive beam optics and ahousing of the electrostatic filter; supplying, from a power supply, afirst voltage and a first current to the plurality of conductive beamoptics during a processing mode; and supplying a second voltage and asecond current to the electrode grid during a cleaning mode to generatea plasma around one or more of the conductive beam optics, wherein theelectrode grid is grounded during the processing mode, and wherein theplurality of conductive beam optics is at zero volts during the cleaningmode.
 16. The method of claim 15, further comprising etching, during thecleaning mode, a deposit formed on one or more of the conductive beamoptics.